People

Willy Hofstetter

Degeneration of bone and cartilage represents a significant problem in Western populations with increasing age expectancy. The origins of the diseases may vary, however, the outcome is often deleterious with severe impact on the health and the quality of life of the patients.

Within the topic of bone metabolism and bone repair, the work of the group is focused on two areas, (i) bone cell biology and (ii) osseointegration of orthopaedic implants and bone substitute materials. Our group found the haematopoietic growth factor CSF-1 to be essential for bone resorption, demonstrating the link between monocyte/macrophage and osteoclast cell lineages (Hofstetter W et al. (1992) PNAS 89:9637; Halasy-Nagy & Hofstetter (1998) J Bone Miner Res 13:1267).

Subsequently we found that inflammatory cytokines, such as tumor necrosis factor-α (TNFα) exert complex effects on bone metabolism by stimulating development of osteoclasts through a direct action on monocyte/macrophage lineage cells, while inhibiting the development of these cells indirectly through osteoblasts by inducing the release of GM-CSF (Balga R et al. (2006) Bone 39:325). Cell biology strategies are also applied to bone repair, since biological functionalization is a promising way to improve osseointegration and turnover of bone substitute materials. Factors like VEGF or RANKL, adsorbed to CaP ceramics are being used to induce bone formation and material removal by cellular and coordinated mechanisms (Klenke FM et al. (2008) J Biomet Mat Res 85:777; Wernike E et al. (2010) Eur Cell Mater 19:30).

Within the frame of the NCCR TransCure, our group will investigate the repertoire of transport molecules expressed by bone cells and will analyze their function during skeletal development and homeostasis.